Does Transcranial Direct Current Stimulation Enhance Exercise-Induced Hypoalgesia?
Description
The present study aimed to investigate if EIH is enhanced by anodal tDCS over the motor cortex. It was hypothesised that an exercise task would produce a greater increase in pain thresholds when preceded by anodal tDCS compared to sham tDCS. An additional aim of this study was to assess the independent effect of tDCS on pain sensitivity. It was hypothesised that anodal tDCS would induce a significant decrease in pain sensitivity when compared to sham stimulation immediately after stimulation. The current study implemented a within-subjects, single-blinded, sham-controlled, randomised block design. Participants were required to attend the laboratory on three separate occasions; a familiarisation session and two experimental sessions corresponding to two different experimental conditions (anodal tDCS, sham tDCS). Study protocols followed those approved by the local human research ethics committee (Project ID: 11882). Each participant visited the laboratory on three separate occasions, with the two experimental conditions presented in a randomised order. Before each session, participants refrained from consuming caffeine or analgesic medications or engaging in vigorous exercise for at least 24 hours. All experimental protocols were conducted in the same temperature controlled (~ 23 ℃, 33% humidity) laboratory. All conditions were separated by at least two days to ensure recovery from the exercise task and to minimise carry-over effects of the stimulation.